So you have created the outline of the deserializer, which is cool. Maybe this ticket could be serve as a kind of tracking ticket for all related smaller tasks? If I get it right we need couple of elements to be added (each could/should likely be a separate tasks), and then simply put it all together in LexemeChangeOpDeserializer (this could be another smaller task). This ticket could be a parent to all those smaller tasks. Once all "subtasks" are done, this could be simply closed.
I am not sure if this makes sense in this case or would it be rather artificial but at least at glance I find it reasonable :)